commons-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Simone Tripodi <simonetrip...@apache.org>
Subject Re: [Graph] Test problems after last commit
Date Sat, 03 Mar 2012 13:34:47 GMT
Hola Marco,

> my doubt is this:  opening a synchronized block into handler implementation on 'this',
 in my opinion is not enough, because the method "CommonsGraph.synchronize()" returns a instance
of the Proxy and not an instance of handler.

true, but *all* methods executions (synchronized and not) are
performed inside the handler, contained in the proxy instance anyway.

So an user cannot use the same "lock"  in order to synchronize a block
like this:

====
Graph g = CommonsGraph.synchronize(g_);
   ...
 synchronized(g) {
     for ( BaseLabeledVertex v2 : g.getVertices() )
     {
         // do somethings
     }
 }
====

I am not sure we can do much more of what we've already done, for that
situation: the snippet below mixes the *data structure*
synchronization with the business logic performed outside.

> So my idea is to open synchronized block inside handler implementation using the same
Proxy instance that the method 'CommonsGraph.synchronize' will return.
> Furthermore I'd like to modify the API by adding also the possibility for the user to
use an your own lock, in that way
>
> CommonsGraph.synchronize( G graph, Object lock )

I have not clear which benefit you want to obtain with that - looks at
Collections#synchronized* methods and see that the separation of
concerns in clear.

> Finally only one question. I think that we should add some tests in order to check the
correct implementation of our multithrading implementation.
> Do you think that we can use an external library in test scope?

Sure that we can, the only issue we have is that GroboUtils is not in
the central repo, adding the external repository would make not easy
having the component released.

best,
-Simo

http://people.apache.org/~simonetripodi/
http://simonetripodi.livejournal.com/
http://twitter.com/simonetripodi
http://www.99soft.org/



On Sat, Mar 3, 2012 at 2:13 PM, Marco Speranza <marcosperanza@apache.org> wrote:
> Morning Simo,
>
> my doubt is this:  opening a synchronized block into handler implementation on 'this',
 in my opinion is not enough, because the method "CommonsGraph.synchronize()" returns a instance
of the Proxy and not an instance of handler.
> So an user cannot use the same "lock"  in order to synchronize a block like this:
>
> ====
> Graph g = CommonsGraph.synchronize(g_);
>    ...
>  synchronized(g) {
>      for ( BaseLabeledVertex v2 : g.getVertices() )
>      {
>          // do somethings
>      }
>  }
> ====
>
> So my idea is to open synchronized block inside handler implementation using the same
Proxy instance that the method 'CommonsGraph.synchronize' will return.
> Furthermore I'd like to modify the API by adding also the possibility for the user to
use an your own lock, in that way
>
> CommonsGraph.synchronize( G graph, Object lock )
>
> WDYT?
>
> Finally only one question. I think that we should add some tests in order to check the
correct implementation of our multithrading implementation.
> Do you think that we can use an external library in test scope?
>
>
> have a nice day
>
>
> --
> Marco Speranza <marcosperanza@apache.org>
> Google Code: http://code.google.com/u/marco.speranza79/
>
> Il giorno 03/mar/2012, alle ore 13:50, Simone Tripodi ha scritto:
>
>> Good morning Marco,
>>
>> I had the chance to have a deeper look at your yesterday's night work
>> and think your additions are good improvements - I just wonder if we
>> can replace the lock object with the handler itself, referencing
>> `this` instead.
>>
>> Thoughts?
>>
>> best and have a nice WE,
>> -Simo
>>
>> http://people.apache.org/~simonetripodi/
>> http://simonetripodi.livejournal.com/
>> http://twitter.com/simonetripodi
>> http://www.99soft.org/
>>
>>
>>
>> On Sat, Mar 3, 2012 at 1:56 AM, Simone Tripodi <simonetripodi@apache.org> wrote:
>>> I saw the commit, please read comments inline.
>>> best,
>>> -Simo
>>>
>>> http://people.apache.org/~simonetripodi/
>>> http://simonetripodi.livejournal.com/
>>> http://twitter.com/simonetripodi
>>> http://www.99soft.org/
>>>
>>>
>>>
>>> On Sat, Mar 3, 2012 at 1:40 AM, Marco Speranza <marcosperanza@apache.org>
wrote:
>>>> Hi I fixed the problem using proxy/handler.
>>>>
>>>> I put also a couple of tests. For do that I insert a test scoped dependency
to a library net.sourceforge.groboutils.groboutils-core
>>>>
>>>> Ciao
>>>>
>>>> --
>>>> Marco Speranza <marcosperanza@apache.org>
>>>> Google Code: http://code.google.com/u/marco.speranza79/
>>>>
>>>> Il giorno 03/mar/2012, alle ore 01:29, Simone Tripodi ha scritto:
>>>>
>>>>> yes, what I didn't understand is how you would like to manage the
>>>>> iterators issue
>>>>>
>>>>> sorry for the brevity but tonight I am getting crazy with at least 3
>>>>> other projects :D
>>>>>
>>>>> -Simo
>>>>>
>>>>> http://people.apache.org/~simonetripodi/
>>>>> http://simonetripodi.livejournal.com/
>>>>> http://twitter.com/simonetripodi
>>>>> http://www.99soft.org/
>>>>>
>>>>>
>>>>>
>>>>> On Sat, Mar 3, 2012 at 1:16 AM, Marco Speranza <marcosperanza@apache.org>
wrote:
>>>>>> I think that we have to use the same patter of java Collections:
a wrapper of Graph/MutableGraph that use a synchronize block.
>>>>>>
>>>>>> WDYT?
>>>>>>
>>>>>> --
>>>>>> Marco Speranza <marcosperanza@apache.org>
>>>>>> Google Code: http://code.google.com/u/marco.speranza79/
>>>>>>
>>>>>> Il giorno 03/mar/2012, alle ore 01:10, Simone Tripodi ha scritto:
>>>>>>
>>>>>>> OK now sounds better, thanks - how would you intend to fix it?
>>>>>>> TIA,
>>>>>>> -Simo
>>>>>>>
>>>>>>> http://people.apache.org/~simonetripodi/
>>>>>>> http://simonetripodi.livejournal.com/
>>>>>>> http://twitter.com/simonetripodi
>>>>>>> http://www.99soft.org/
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On Sat, Mar 3, 2012 at 1:01 AM, Marco Speranza <marcosperanza@apache.org>
wrote:
>>>>>>>>>>
>>>>>>>>>> furthermore there is another problem: with handler
is not possible to use correctly synchronization block like this
>>>>>>>>>>
>>>>>>>>>> ====
>>>>>>>>>> Graph g = CommonsGraph.synchronize(g_);
>>>>>>>>>>     ...
>>>>>>>>>>  synchronized(g) {
>>>>>>>>>>       for ( BaseLabeledVertex v2 : g.getVertices()
)
>>>>>>>>>>       {
>>>>>>>>>>           // do somethings
>>>>>>>>>>       }
>>>>>>>>>>  }
>>>>>>>>>> ====
>>>>>>>>>
>>>>>>>>> sorry I don't understand what you meant/intend to do
>>>>>>>>
>>>>>>>> I'm trying to explain better. the method getVertices return
an Iterator. In a multi-thread environment you have to ensure that during the 'for' execution
the [graph] data structure remains  consistent.
>>>>>>>> Also for java collection is the same [http://docs.oracle.com/javase/6/docs/api/java/util/Collections.html#synchronizedCollection(java.util.Collection)]
>>>>>>>>
>>>>>>>> So if we use a proxy/handler there is no way to "export"
the mutex/lock variable used into handler class.
>>>>>>>>
>>>>>>>> In  our CommonsGraph the variable this.lock is private and
is non possible to export out of the method, so the user can not utilize the lock to synchronize
his block.
>>>>>>>>
>>>>>>>> ===
>>>>>>>>        public Object invoke( Object proxy, Method method,
Object[] args )
>>>>>>>>            throws Throwable
>>>>>>>>        {
>>>>>>>>            if ( synchronizedMethods.contains( method
) )
>>>>>>>>            {
>>>>>>>>                try
>>>>>>>>                {
>>>>>>>>                    synchronized ( this.lock )
>>>>>>>>                    {
>>>>>>>>                        return method.invoke(
synchronizedMethods, args );
>>>>>>>>                    }
>>>>>>>>                }
>>>>>>>>                catch ( InvocationTargetException
e )
>>>>>>>>                {
>>>>>>>>                    throw e.getTargetException();
>>>>>>>>                }
>>>>>>>>            }
>>>>>>>>            return method.invoke( synchronizedMethods,
args );
>>>>>>>>        }
>>>>>>>> ===
>>>>>>>>
>>>>>>>> ciao
>>>>>>>>
>>>>>>>> --
>>>>>>>> Marco Speranza <marcosperanza@apache.org>
>>>>>>>> Google Code: http://code.google.com/u/marco.speranza79/
>>>>>>>>
>>>>>>>> Il giorno 03/mar/2012, alle ore 00:45, Simone Tripodi ha
scritto:
>>>>>>>>
>>>>>>>>>> furthermore there is another problem: with handler
is not possible to use correctly synchronization block like this
>>>>>>>>>>
>>>>>>>>>> ====
>>>>>>>>>> Graph g = CommonsGraph.synchronize(g_);
>>>>>>>>>>     ...
>>>>>>>>>>  synchronized(g) {
>>>>>>>>>>       for ( BaseLabeledVertex v2 : g.getVertices()
)
>>>>>>>>>>       {
>>>>>>>>>>           // do somethings
>>>>>>>>>>       }
>>>>>>>>>>  }
>>>>>>>>>> ====
>>>>>>>>>
>>>>>>>>> sorry I don't understand what you meant/intend to do
>>>>>>>>>
>>>>>>>>>> I really think that a synchronized wrapper it's the
best solution.
>>>>>>>>>>
>>>>>>>>>> WDYT?
>>>>>>>>>
>>>>>>>>> they sucks because we have to keep them updated while
, but if there
>>>>>>>>> are not alternatives...
>>>>>>>>> -Simo
>>>>>>>>>
>>>>>>>>> http://people.apache.org/~simonetripodi/
>>>>>>>>> http://simonetripodi.livejournal.com/
>>>>>>>>> http://twitter.com/simonetripodi
>>>>>>>>> http://www.99soft.org/
>>>>>>>>>
>>>>>>>>> ---------------------------------------------------------------------
>>>>>>>>> To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
>>>>>>>>> For additional commands, e-mail: dev-help@commons.apache.org
>>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> ---------------------------------------------------------------------
>>>>>>>> To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
>>>>>>>> For additional commands, e-mail: dev-help@commons.apache.org
>>>>>>>>
>>>>>>>
>>>>>>> ---------------------------------------------------------------------
>>>>>>> To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
>>>>>>> For additional commands, e-mail: dev-help@commons.apache.org
>>>>>>>
>>>>>>
>>>>>>
>>>>>> ---------------------------------------------------------------------
>>>>>> To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
>>>>>> For additional commands, e-mail: dev-help@commons.apache.org
>>>>>>
>>>>>
>>>>> ---------------------------------------------------------------------
>>>>> To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
>>>>> For additional commands, e-mail: dev-help@commons.apache.org
>>>>>
>>>>
>>>>
>>>> ---------------------------------------------------------------------
>>>> To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
>>>> For additional commands, e-mail: dev-help@commons.apache.org
>>>>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
>> For additional commands, e-mail: dev-help@commons.apache.org
>>
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
> For additional commands, e-mail: dev-help@commons.apache.org
>

---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
For additional commands, e-mail: dev-help@commons.apache.org


Mime
View raw message